Lots of people these days get their exercise at gyms and health clubs, oftentimes by walking or running on treadmills.
If you've ever been on a treadmill for ten minutes or more and then suddenly stepped off it, you've probably experienced the weird sensation that you are suddenly moving much faster than you think you should be.
This happens because when you're on the treadmill, during the first ten minutes, your brain is processing the fact that you're moving quickly while what you're seeing remains stationary. After ten minutes, the brain stops associating walking (and/or running) with moving from location to location.
So, the brain recalibrates its internal sense of motion to perceive that objects are moving quickly even when moving slowly . In simple terms, your brain tells itself: this is how fast objects move by when I'm walking at this rate, as opposed to what was formerly the case.
That means when you step off the treadmill and begin actually moving through space again, your recalibrated brain is giving off a false sense of acceleration. What the legs say and what the eyes say is out of sync.
The sensation of accelerated motion is only temporary, though, and the ever-adaptable brain soon readjusts itself once more – until the next time you step up on that rolling, immobile track.
"Fast Feet, Slow Brains." Discover Magazine. September 01, 1996. Accessed October 31, 2016.